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24 pages, 10209 KiB

Open AccessArticle

A Simulation Study on the Effect of Supersonic Ultrasonic Acoustic Streaming on Solidification Dendrite Growth Behavior During Laser Cladding Based on Boundary Coupling

by Xing Han, Hao Zhan, Chang Li, Xuan Wang, Jiabo Liu, Shuchao Li, Qian Sun and Fanhong Kong

Coatings 2024, 14(11), 1381; https://doi.org/10.3390/coatings14111381 - 30 Oct 2024

Viewed by 186

Abstract

Laser cladding has unique technical advantages, such as precise heat input control, excellent coating properties, and local selective cladding for complex shape parts, which is a vital branch of surface engineering. During the laser cladding process, the parts are subjected to extreme thermal [...] Read more.

Laser cladding has unique technical advantages, such as precise heat input control, excellent coating properties, and local selective cladding for complex shape parts, which is a vital branch of surface engineering. During the laser cladding process, the parts are subjected to extreme thermal gradients, leading to the formation of micro-defects such as cracks, pores, and segregation. These defects compromise the serviceability of the components. Ultrasonic vibration can produce thermal, mechanical, cavitation, and acoustic flow effects in the melt pool, which can comprehensively affect the formation and evolution for the microstructure of the melt pool and reduce the microscopic defects of the cladding layer. In this paper, the coupling model of temperature and flow field for the laser cladding of 45 steel 316L was established. The transient evolution laws of temperature and flow field under ultrasonic vibration were revealed from a macroscopic point of view. Based on the phase field method, a numerical model of dendrite growth during laser cladding solidification under ultrasonic vibration was established. The mechanism of the effect of ultrasonic vibration on the solidification dendrite growth during laser cladding was revealed on a mesoscopic scale. Based on the microstructure evolution model of the paste region in the scanning direction of the cladding pool, the effects of a static flow field and acoustic flow on dendrite growth were investigated. The results show that the melt flow changes the heat and mass transfer behaviors at the solidification interface, concurrently changing the dendrites’ growth morphology. The acoustic streaming effect increases the flow velocity of the melt pool, which increases the tilt angle of the dendrites to the flow-on side and promotes the growth of secondary dendrite arms on the flow-on side. It improves the solute distribution in the melt pool and reduces elemental segregation. Full article

(This article belongs to the Special Issue Effects of Laser Treatment on Surface Characterization and Mechanical Properties of Alloys)

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11 pages, 3032 KiB

Open AccessArticle

Simulation of Dendrite Remelting via the Phase-Field Method

by Xing Han, Chang Li, Hao Zhan, Shuchao Li, Jiabo Liu, Fanhong Kong and Xuan Wang

Coatings 2024, 14(11), 1364; https://doi.org/10.3390/coatings14111364 - 27 Oct 2024

Viewed by 336

Abstract

The solidification of alloys is a key physical phenomenon in advanced material-processing techniques including, but not limited to, casting and welding. Mastering and controlling the solidification process and the way in which microstructure evolution occurs constitute the key to obtaining excellent material properties. [...] Read more.

The solidification of alloys is a key physical phenomenon in advanced material-processing techniques including, but not limited to, casting and welding. Mastering and controlling the solidification process and the way in which microstructure evolution occurs constitute the key to obtaining excellent material properties. The microstructure of a solidified liquid metal is dominated by dendrites. The growth process of these dendrites is extremely sensitive to temperature changes, and even a small change in temperature can significantly affect the growth rate of the dendrite tip. Dendrite remelting is inevitable when the temperature exceeds the critical threshold. In this study, a temperature-induced-dendrite remelting model was established, which was implemented through the coupling of the phase field method (PFM) and finite difference method (FDM). The transient evolution law of dendrite remelting was revealed by simulating dendritic growth and remelting processes. The phase field model showed that the lateral dendrites melt first, the main dendrites melt later, and the main dendrites only shrink but do not melt when the lateral dendrites have not completely melted or the root is not broken. The long lateral branches break into fragments, while the short lateral branches shrink back into the main dendrites. The main dendrites fracture and melt in multiple stages due to inhomogeneity. Full article

(This article belongs to the Special Issue Effects of Laser Treatment on Surface Characterization and Mechanical Properties of Alloys)

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20 pages, 7384 KiB

Open AccessArticle

Evolutionary Mechanism of Solidification Behavior in the Melt Pool During Disk Laser Cladding with 316L Alloy

by Chang Li, Jiabo Liu, Shuchao Li, Fanhong Kong, Xuan Wang, Han Sun and Yichang Sun

Coatings 2024, 14(10), 1337; https://doi.org/10.3390/coatings14101337 - 18 Oct 2024

Viewed by 387

Abstract

Laser cladding is an emerging environmentally friendly surface-strengthening technology. During the cladding process, the changes in molten pool temperature and velocity directly affect the solidification process and element distribution. The quantitative revelation of the directional solidification mechanism in the molten pool during the [...] Read more.

Laser cladding is an emerging environmentally friendly surface-strengthening technology. During the cladding process, the changes in molten pool temperature and velocity directly affect the solidification process and element distribution. The quantitative revelation of the directional solidification mechanism in the molten pool during the cladding process is crucial for enhancing the quality of the cladding layer. In this study, a multi-field coupling numerical model was developed to simulate the coating process of 316L powder on 45 steel matrices using a disk laser. The instantaneous evolution law of the temperature and flow fields was derived, providing input conditions for simulating microstructure evolution in the molten pool’s paste zone. The behavior characteristics of the molten pool were predicted through numerical simulation, and the microstructure evolution was simulated using the phase field method. The phase field model reveals that dendrite formation in the molten pool follows a sequence of plane crystal growth, cell crystal growth, and columnar crystal growth. The dendrites can undergo splitting to form algal structures under conditions of higher cooling rates and lower temperature gradients. The scanning speed of laser cladding (6 mm/s) has minimal impact on dendrite growth; instead, convection within the molten pool primarily influences dendrite growth and tilt and solute distribution. Full article

(This article belongs to the Special Issue Effects of Laser Treatment on Surface Characterization and Mechanical Properties of Alloys)

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18 pages, 26175 KiB

Open AccessArticle

Influence of Scanning Paths on the Weld Pool Behavior, Microstructure, and Mechanical Property of AA2060 Al-Li Alloy Joints by Laser Beam Oscillation Welding

by Yanbo Song, Ying Liang, Hongbing Liu, Luchan Lin, Yanfeng Gao, Hua Zhang and Jin Yang

Coatings 2024, 14(8), 1065; https://doi.org/10.3390/coatings14081065 - 20 Aug 2024

Viewed by 758

Abstract

In this paper, the laser beam oscillation welding (LBOW) was utilized to weld a 2 mm thick AA2060 aluminum-lithium (Al-Li) alloy plate. The weld pool behaviors under three scanning paths (pure laser, O-shaped, and ∞-shaped) were investigated. It was observed that the O-shaped [...] Read more.

In this paper, the laser beam oscillation welding (LBOW) was utilized to weld a 2 mm thick AA2060 aluminum-lithium (Al-Li) alloy plate. The weld pool behaviors under three scanning paths (pure laser, O-shaped, and ∞-shaped) were investigated. It was observed that the O-shaped scanning path resulted in the most stable welding process. In addition, the weld macroscopic formation, microstructure, and mechanical property between different paths were studied. The results showed that pure laser and ∞-shaped patterns produced welding defects such as spatters and collapse during the welding process, while the O-shaped pattern exhibited good macroscopic formation at varying laser powers. The O-shaped pattern promoted the finest grain in the weld center and reduced the heat input during the welding process. The equiaxed grain zone (EQZ) width of the O-shaped pattern is the smallest compared to the other two patterns at high laser power. In addition to this, the O-shaped pattern could effectively reduce the porosity in the weld. When an O-shaped scanning pattern was adopted at the ideal laser power parameter of 3000 W, the microhardness of the weld center increased by approximately 5.6% compared to pure laser mode. Full article

(This article belongs to the Special Issue Effects of Laser Treatment on Surface Characterization and Mechanical Properties of Alloys)

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16 pages, 7703 KiB

Open AccessArticle

Experimental Analysis and Wear Prediction Model Based on Friction Heat for Dry Sliding Contact

by Qiming Sun and Dayu Zheng

Coatings 2024, 14(6), 742; https://doi.org/10.3390/coatings14060742 - 12 Jun 2024

Viewed by 1056

Abstract

In this study, the influence of the frictional heat effect on the degree of wear is explored from the perspectives of initial contact positive pressure and frictional relative slip velocity. Experiments based on a multifunctional friction and wear machine show that the friction [...] Read more.

In this study, the influence of the frictional heat effect on the degree of wear is explored from the perspectives of initial contact positive pressure and frictional relative slip velocity. Experiments based on a multifunctional friction and wear machine show that the friction temperature increases with an increase in friction relative velocity and initial normal contact load, which exacerbates the frictional thermal expansion and normal load fluctuation, and with the generation of frictional heat, the normal force fluctuates periodically; the wear mass and temperature in the contact area iterate cyclically, which results in the wear mass increasing. 316L stainless steel, 5A06 aluminium alloy and pure titanium are used in the Archard wear model due to their applications in severe wear environments. Since 316L stainless steel, 5A06 aluminium alloy and pure titanium are mostly used in wear-intensive environments, the Archard wear model is optimised based on the frictional heat effect of these three materials, and the accuracy of the improved model in 316L stainless steel, 5A06 aluminium alloy and pure titanium is improved by 52.6%, 7.4% and 23.9%, respectively, when compared with the conventional model. This study lays a theoretical foundation for the wear prediction models of 316L stainless steel, 5A06 aluminium alloy and pure titanium. Full article

(This article belongs to the Special Issue Effects of Laser Treatment on Surface Characterization and Mechanical Properties of Alloys)

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21 pages, 11013 KiB

Open AccessArticle

Macroscopic Characteristic and Properties of Inconel 625 Cladding Layers on a Cylinder Liner Based on Laser Cladding Assisted by a Steady-State Magnetic Field

by Xinlin Wang, Jing Zhu, Yongchang Tian, Jinkun Jiang and Tianmin Guan

Coatings 2024, 14(4), 438; https://doi.org/10.3390/coatings14040438 - 7 Apr 2024

Cited by 1 | Viewed by 1038

Abstract

Cylinder liners, which are an vital part of marine diesel engines, are prone to damage owing to the pool working conditions of reciprocating friction and electrochemical corrosion. As a burgeoning manufacturing technology, laser cladding has a prospective application on repairing and performance enhancement [...] Read more.

Cylinder liners, which are an vital part of marine diesel engines, are prone to damage owing to the pool working conditions of reciprocating friction and electrochemical corrosion. As a burgeoning manufacturing technology, laser cladding has a prospective application on repairing and performance enhancement of cylinder liners. The performance of cladding layers on cylinder liners reported by current studies is not satisfactory. The laser cladding, assisted by the steady state magnetic field on the cylinder liner, is an effectual method to cover the shortage. However, there are few studies about that. In this study, single-track Inconel 625 cladding layers were carried out on a cylinder liner, assisted by a steady-state magnetic field. The effects of the magnetic field intensity and direction on the geometrical characteristics (width, height, penetration, and dilution ratio), microstructure, phase composition, microhardness, wear resistance, and corrosion resistance were investigated. According to the results obtained, adding a magnetic field with a small magnetic field intensity can significantly enhance the flatness, hardness, friction, wear resistance, and corrosion resistance of the cladding layer. Applying a magnetic field in the horizontal direction was conducive to improving the corrosion resistance of the sample. With the application of a vertical magnetic field, the microhardness increased, and wear resistance, as well as the flatness of the cladding layer, were improved. Full article

(This article belongs to the Special Issue Effects of Laser Treatment on Surface Characterization and Mechanical Properties of Alloys)

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22 pages, 3879 KiB

Open AccessArticle

Influence of Scanning Strategy and Post-Treatment on Cracks and Mechanical Properties of Selective-Laser-Melted K438 Superalloy

by Bin Zhang, Hua Yan, Zhisheng Xia, Peilei Zhang, Haichuan Shi and Qinghua Lu

Coatings 2024, 14(4), 414; https://doi.org/10.3390/coatings14040414 - 30 Mar 2024

Viewed by 1021

Abstract

The feasibility of manufacturing high-performance components with complex structures is limited due to cracks in some superalloys fabricated by selective laser melting (SLM). By controlling the main process parameters such as scanning strategy, the adverse effects of cracks can be effectively reduced. In [...] Read more.

The feasibility of manufacturing high-performance components with complex structures is limited due to cracks in some superalloys fabricated by selective laser melting (SLM). By controlling the main process parameters such as scanning strategy, the adverse effects of cracks can be effectively reduced. In this paper, the effects of two different SLM scanning strategies with island and ‘back-and-forth’ and post-heat treatment on the cracks and mechanical properties of selective-laser-melted (SLMed) K438 alloy were investigated. The results show that the SLM method of the ‘back-and-forth’ scanning strategy had better lap and interlayer rotation angles and a more uniform distribution of laser energy compared with the island scanning strategy. The residual stress accumulation was reduced and crack formation was inhibited under this scanning strategy owing to the cooling and shrinkage process. In addition, the dislocation motion was hindered by the formation of uniformly dispersed MC carbides and γ’ phases during the SLM K438 alloy process, which resulted in the density of the as-built SLMed K438 alloy being up to 99.34%, the hardness up to 9.6 Gpa, and the tensile strength up to 1309 MPa. After post-heat treatment, the fine secondary γ’ phases were precipitated and dispersed uniformly in the Ni matrix, which effectively improved the Young’s modulus and tensile strength of the alloy by dispersing the stress-concentrated area. Full article

(This article belongs to the Special Issue Effects of Laser Treatment on Surface Characterization and Mechanical Properties of Alloys)

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18 pages, 5945 KiB

Open AccessArticle

Microstructure and Impact Toughness of Laser-Arc Hybrid Welded Joint of Medium-Thick TC4 Titanium Alloy

by Peng Luo, Wanxi Feng, Gang Zu, Linyin Luo and Jun Xiao

Coatings 2024, 14(4), 395; https://doi.org/10.3390/coatings14040395 - 27 Mar 2024

Cited by 1 | Viewed by 1374

Abstract

This study delves into the impact toughness of medium-thick (12 mm thick) titanium alloy joints crafted through a multi-layer, multi-pass welding technique that blends laser-arc (MIG) hybrid welding technology. Microstructural scrutiny, employing optical microscopy, SEM and TEM, unveils a consistent composition across weld [...] Read more.

This study delves into the impact toughness of medium-thick (12 mm thick) titanium alloy joints crafted through a multi-layer, multi-pass welding technique that blends laser-arc (MIG) hybrid welding technology. Microstructural scrutiny, employing optical microscopy, SEM and TEM, unveils a consistent composition across weld passes, with prevailing α/α′ phases interspersed with some β phase, resulting in basket-weave structures primarily dominated by acicular α′ martensite. However, upper regions exhibit Widmanstatten microstructures, potentially undermining joint toughness. Hardness testing indicates higher values in cosmetic layers (~420 HV) compared to backing layers and bending tests manifest superior toughness in lower joint regions, attributed to smaller grain sizes induced by repetitive welding thermal cycles. Impact toughness assessment unveils diminished values in the weld metal (WM) compared to the heat-affected zone (HAZ) and base material (BM), amounting to 91.3% of the base metal’s absorption energy. This decrement is ascribed to heightened porosity in upper regions and variations in grain size and phase composition due to multi-layer, multi-pass welding. Microstructural analysis proximal to failure sites suggests one mechanism wherein crack propagation is impeded by the β phase at acute crack angles. In essence, this study not only underscores the practicality of laser-MIG hybrid welding for medium-thick TC4 alloy plates but also underscores the reliability of joint mechanical properties. Full article

(This article belongs to the Special Issue Effects of Laser Treatment on Surface Characterization and Mechanical Properties of Alloys)

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21 pages, 6716 KiB

Open AccessArticle

Post-Wear Surface Morphology Assessment of Selective Laser Melting (SLM) AlSi10Mg Specimens after Heat Exposure to Different Gas Flames

by Maaz Akhtar, Muhammad Muzamil, Muhammad Samiuddin, Naser Alsaleh, Rashid Khan, Mahad Ali Khan, Joy Djuansjah, Ali Khursheed Siddiqui and Arfan Majeed

Coatings 2024, 14(3), 252; https://doi.org/10.3390/coatings14030252 - 20 Feb 2024

Cited by 3 | Viewed by 1220

Abstract

The wear surface morphology of AlSi10Mg specimens, originally manufactured using selective laser melting (SLM), has been analyzed in the context of exposure to heat from gas flames. The first stage of the experimental work included the performance of surface heat-exposure on SLM-prepared specimens [...] Read more.

The wear surface morphology of AlSi10Mg specimens, originally manufactured using selective laser melting (SLM), has been analyzed in the context of exposure to heat from gas flames. The first stage of the experimental work included the performance of surface heat-exposure on SLM-prepared specimens through oxyacetylene gas welding. Gas welding was utilized with three different flames, namely; reducing, neutral, and oxidizing on the as-built specimens of SLM. The post-surface-treated specimens were subjected to pin-on-disk wear testing against fixed parameters. After the performance of wear testing at two different radii, the mass loss of each of the four types of specimens was calculated including the three specimens exposed to heat along with the as-built specimens. The results showed that the maximum amount of mass losses at 24 mm and 30 mm radii belongs to the neutral flame specimens and the least was for the as-built condition specimens. Upon analysis, the heat-exposure specimens through all three types of gas flames resulted in an increase in the amount of mass in contrast to the as-built specimens. Moreover, the morphologies of the developed wear tracks at surfaces were examined using the scanning electron microscope (SEM) for the understating of the mechanism. Full article

(This article belongs to the Special Issue Effects of Laser Treatment on Surface Characterization and Mechanical Properties of Alloys)

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12 pages, 10954 KiB

Open AccessArticle

Adhesion Strength and Anti-Corrosion Performance of Ceramic Coating on Laser-Textured Aluminum Alloy

by Changfeng Fan, Xue Wang, Xiaoli Yin, Wei Huang, Yujie Da, Hao Jiang, Jingfeng Cao, Yongchao Gai and Wangwang Zhang

Coatings 2023, 13(12), 2098; https://doi.org/10.3390/coatings13122098 - 17 Dec 2023

Cited by 1 | Viewed by 1813

Abstract

Laser surface texturing and micro-arc oxidation provide excellent approaches to enhance the adhesion strength and anti-corrosion performance of adhesive bonding interfaces in aluminum alloys, which can be applied in the field of automotive light weighting. Herein, micro-arc oxidation coatings were fabricated on the [...] Read more.

Laser surface texturing and micro-arc oxidation provide excellent approaches to enhance the adhesion strength and anti-corrosion performance of adhesive bonding interfaces in aluminum alloys, which can be applied in the field of automotive light weighting. Herein, micro-arc oxidation coatings were fabricated on the laser-textured aluminum surface under the voltage of 500 V for various treatment times (5 min, 15 min, 30 min, 60 min). The anti-corrosion performance of ceramic coatings on the laser-textured surface was analyzed using electrochemical measurements. The results of electrochemical measurement indicate that the coating on the sample surface presents two time constants corresponding to a dual-layer structure. The sample grown under 500 V for 60 min exhibits excellent protective performance with a value of 1.3 × 10⁷ ohm·cm². The adhesion strength of laser-textured ceramic coating is improved compared with the as-received substrate. The sample treated with 500 V for 30 min exhibits the highest bonding strength with a value of 52 MPa. The wider pores and bulges for the sample grown in 60 min would introduce microcracks and consequently reduce the adhesion strength. Full article

(This article belongs to the Special Issue Effects of Laser Treatment on Surface Characterization and Mechanical Properties of Alloys)

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11 pages, 7406 KiB

Open AccessArticle

An Analysis of the Morphology Evolution of YG8 Cemented Carbide by Laser Ablation in the Liquid Phase

by Yujie Fan, Kang Zhao, Mengjie Hao, Jing Xia, Xiaoyan Guan and Fanghua Liu

Coatings 2023, 13(12), 2061; https://doi.org/10.3390/coatings13122061 - 9 Dec 2023

Viewed by 996

Abstract

To explore the influence of the number of laser ablations on the shape, geometry, and taper of the pitting structure by laser ablation in the liquid phase, three-dimensional confocal microscopy was used to quantitatively characterize the shape of the surface dotting texture of [...] Read more.

To explore the influence of the number of laser ablations on the shape, geometry, and taper of the pitting structure by laser ablation in the liquid phase, three-dimensional confocal microscopy was used to quantitatively characterize the shape of the surface dotting texture of YG8 cemented carbide and analyze the evolution of the morphology based on the liquid-assisted laser ablation test. The results show that the surface pitting structure of YG8 cemented carbide evolves from a micro-convexity to a crater with the increase in the number of laser ablations, and the bottom of the crater produces a convexity after 7 ablations, the shape of the crater evolves to a trapezoidal shape after 13 ablations, and the shape is stable. The size of the dot texture increases with the number of laser ablations and reaches a maximum value of 396 μm in diameter and 149 μm in depth at the 10th and 12th ablations, respectively. The taper of the dot texture showed a trend of decreasing, increasing, and then decreasing with the increase in the number of laser ablations, and the taper was stable with more than seven ablations. This study lays a theoretical foundation for the control of the dot texture morphology on the surface of YG8 cemented carbide by laser ablation in a liquid-phase environment. Full article

(This article belongs to the Special Issue Effects of Laser Treatment on Surface Characterization and Mechanical Properties of Alloys)

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10 pages, 3454 KiB

Open AccessArticle

Effects of Nanosecond-Pulsed Laser Milling on the Surface Properties of Al₂O₃ Ceramics

by Zhaomei Xu, Zhengye Zhang, Qi Sun, Jiale Xu, Zhao Meng, Yizhi Liu and Xiankai Meng

Coatings 2022, 12(11), 1687; https://doi.org/10.3390/coatings12111687 - 6 Nov 2022

Cited by 1 | Viewed by 1272

Abstract

The effect of nanosecond-pulsed laser milling on the surficial microstructure of Al₂O₃ ceramics is studied in this work. The macrostructure, microstructure, surface roughness, and milling depth of the ceramics are analyzed via scanning electron microscopy and confocal laser scanning microscopy. [...] Read more.

The effect of nanosecond-pulsed laser milling on the surficial microstructure of Al₂O₃ ceramics is studied in this work. The macrostructure, microstructure, surface roughness, and milling depth of the ceramics are analyzed via scanning electron microscopy and confocal laser scanning microscopy. The results reveal that the surface roughness and the milling depth of Al₂O₃ ceramics increase with increasing laser power, laser repetition rate, and scanning times. After nanosecond-pulsed laser milling, cavities as well as molten and granular solidified structures are observed on the Al₂O₃ ceramic surface, which indicate that the main mechanism of nanolaser milling is the melting and gasification caused by the interaction between the laser and the material. Full article

(This article belongs to the Special Issue Effects of Laser Treatment on Surface Characterization and Mechanical Properties of Alloys)

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Review

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24 pages, 7804 KiB

Open AccessReview

Progress in Microstructure Design and Control of High-Hardness Fe-Based Alloy Coatings via Laser Cladding

by Lipei Liu, Yinghua Lin, Longsheng Peng, Xin Kang and Xinlin Wang

Coatings 2024, 14(11), 1351; https://doi.org/10.3390/coatings14111351 - 24 Oct 2024

Viewed by 432

Abstract

High-hardness iron-based alloy coatings are extensively utilized in aerospace, automotive, and industrial equipment due to their exceptional wear resistance and long service life. Laser cladding has emerged as one of the primary techniques for fabricating these coatings, owing to its rapid cooling and [...] Read more.

High-hardness iron-based alloy coatings are extensively utilized in aerospace, automotive, and industrial equipment due to their exceptional wear resistance and long service life. Laser cladding has emerged as one of the primary techniques for fabricating these coatings, owing to its rapid cooling and dense microstructure characteristics. However, the production of high-hardness iron-based alloy coatings via laser cladding continues to face numerous challenges, particularly when controlling the morphology, quantity, and distribution of the reinforcing phases, which can lead to cracking during processing and service, thus compromising their usability. The cracks of the cladding layer will be suppressed through good microstructure design and control, resulting in a wide range of performance for high-hardness Fe-based alloy coatings. This paper reviews recent advancements in the design and control of the organization and structure of high-hardness iron-based alloy coatings from the perspectives of material composition, processing parameters, and external assistance techniques. It summarizes the properties and applications of various materials, including different alloying elements, ceramic particles, and rare earth oxides, while systematically discussing how processing parameters influence microstructure and performance. Additionally, the mechanisms by which external auxiliary energy fields affect the melt pool and solidified microstructure during laser cladding are elucidated. Finally, the future development directions of laser cladding technology for high-hardness iron-based coatings are anticipated, emphasizing the need for further quantification of the optimal coupling relationships among the gain effects of composite energy fields. Full article

(This article belongs to the Special Issue Effects of Laser Treatment on Surface Characterization and Mechanical Properties of Alloys)

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20 pages, 3582 KiB

Open AccessReview

Progress on the Properties of Ceramic Phase-Reinforced High-Entropy Alloy Composite Coatings Produced via Laser Cladding

by Haoran Zhang, Yaowei Yong, Fuwei Wang, Yuan Liang, Lin Liu, Hong Liu and Yang Gao

Coatings 2024, 14(1), 127; https://doi.org/10.3390/coatings14010127 - 18 Jan 2024

Cited by 4 | Viewed by 2767

Abstract

The production of ceramic phase-reinforced high-entropy alloy composite coatings with excellent mechanical properties, high-temperature oxidation resistance, and corrosion resistance via laser cladding is a new hotspot in the field of surface engineering. However, as high-entropy alloys have a wide range of constituent systems [...] Read more.

The production of ceramic phase-reinforced high-entropy alloy composite coatings with excellent mechanical properties, high-temperature oxidation resistance, and corrosion resistance via laser cladding is a new hotspot in the field of surface engineering. However, as high-entropy alloys have a wide range of constituent systems and different kinds of ceramic particles are introduced in different ways that give the coatings unique microscopic organization, structure, and synthesized performance, it is necessary to review the methods of preparing ceramic phase-reinforced high-entropy alloys composite coatings via laser cladding. In this paper, the latest research progress on laser cladding technology in the preparation of ceramic phase-reinforced high-entropy alloy composite coatings is first reviewed. On this basis, the effects of ceramic particles, alloying elements, process parameters, and the microstructure and properties of the coatings are analyzed with the examples of the in situ generation method and the externally added method. Finally, research gaps and future trends are pointed out, serving as a reference for the subsequent research, application, and development of the preparation of ceramic phase-reinforced high-entropy alloy composite coatings. Full article

(This article belongs to the Special Issue Effects of Laser Treatment on Surface Characterization and Mechanical Properties of Alloys)

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23 pages, 4370 KiB

Open AccessReview

Macroscopic and Microstructural Features of Metal Thin-Wall Fabricated by Laser Material Deposition: A Review

by Xinlin Wang, Jinkun Jiang, Chengui Xia and Yang Yu

Coatings 2022, 12(8), 1104; https://doi.org/10.3390/coatings12081104 - 3 Aug 2022

Cited by 3 | Viewed by 1914

Abstract

Owing to the versatility without expanding the machine’s size, thin-wall has been widely used in high-value parts. The investigation of laser additive manufacturing (LAM), which has advantages such as high powder density, easy controllability, and excellent stability, on the fabrication of thin-wall has [...] Read more.

Owing to the versatility without expanding the machine’s size, thin-wall has been widely used in high-value parts. The investigation of laser additive manufacturing (LAM), which has advantages such as high powder density, easy controllability, and excellent stability, on the fabrication of thin-wall has drawn much attention. In this paper, the research status of macroscopic and microstructural features of metal thin-wall fabricated by LAM has been reviewed. The deposition quality was mainly focused on the effect of process parameters and especially the matching of z-increment and single deposition height. Based on the grain size and growth of columnar, the characteristics of microstructures were analyzed. Considering the structural feature of thin-wall, the effect of grain size and phases on the hardness and distribution of hardness were discussed. The effect of grain size, phases and loading direction on the tensile properties were reviewed. The distribution and modification of thermal stress were presented. Full article

(This article belongs to the Special Issue Effects of Laser Treatment on Surface Characterization and Mechanical Properties of Alloys)

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